This invention relates to avionics systems, flight displays, and more particularly to enhancements in the display of a vertical terrain profile (VTP) on an avionics flight display for providing a real-time, dynamic display of any terrain hazards so as to prevent controlled flight into terrain (CFIT). Controlled flight into terrain continues to plague air travel as one of the leading causes of fatal aircraft crashes.
Improved methods of alerting a flight crew of potential CFIT conditions have been developed as a result of technology advancements. These technology enhancements include accurate aircraft present position information, terrain data and suitable storage means, and computer processing resources. One such improved alerting system is referred to as a Ground Collision Avoidance System (GCAS). The GCAS system utilizes aircraft present position information, aircraft state information, and a digital terrain database to determine a flight path of an aircraft relative to the surrounding terrain. Such a system is described in U.S. Pat. No. 4,224,669 herein incorporated by reference in its entirety.
Terrain awareness displays that use a format that provides a pilot or flight crew with complete situational awareness of potential terrain hazards to the aircraft are known. Positional information and terrain data in a database are used to display horizontal and vertical terrain information on a flight display. The information is formatted to provide an interface that provides the data conveniently, simply, and intuitively in a format that is easily assimilated and interpreted by a human operator. Such a terrain awareness display is disclosed in U.S. Pat. No. 5,936,552 herein incorporated by reference in its entirety. Shown in this reference is a vertical terrain profile for a terrain path in a line directly in front of the aircraft out to a selected distance.
Vertical terrain profiles may be shown on primary flight displays (PFD) and multifunction displays (MFD) or other display means on an aircraft. What is typically presented to a pilot on a PFD or MFD is a vertical terrain profile in front of an aircraft out to a preselected range. A problem with the vertical terrain profile is that the terrain representation is interpreted through software routines that automatically define a swathe along and either side of the aircraft horizontal flight path or heading/track. This swathe is predefined and the pilot has no control over its width. Moreover, the swathe is completely hidden from the pilot who has no visual cue as to the swathe width currently being used to interpret the terrain data.
What is needed is vertical terrain profile display that displays swathe width information in various formats and allows a pilot to select the swathe width to further enhance the situation awareness of a pilot to prevent CFIT accidents.
A flight display for use in an avionics system is disclosed. The flight display has a visual display format to show an enhanced vertical situation of an aircraft comprising a vertical terrain profile display of terrain in front of the aircraft over a selected range and a selected swathe width. The vertical terrain profile display shows a side-on terrain profile view that includes a digital display of the selected swathe width and a digital display of range in front of the aircraft in predetermined increments up to the selected range. The flight display includes a plan view of the aircraft position that further comprises swathe lines on either side of an aircraft showing the selected swathe width. The flight display also includes a means for selecting the swathe width.
The flight display also includes means for changing the vertical terrain profile display into a end-on vertical terrain profile view over the selected swathe width. The end-on terrain profile view also includes a digital display of the selected range and a digital display of the selected swathe width on each side of the aircraft on the end-on terrain profile view.
The flight display plan view may be a compass display with the swathe lines projecting forward and parallel to an aircraft heading/track. The plan view may also be a map display with the swathe lines following an aircraft flight path.
The side-on terrain profile view, the end-on terrain profile view, and the swathe lines may be shown in red on the vertical terrain profile display when the terrain is at or above an aircraft altitude.
The means for selecting the swathe width and for changing the vertical terrain profile display may be a knob, joystick, toggle switch, pushbutton or line select key.
It is an object of the present invention to enhance situational awareness of a pilot by providing enhanced vertical terrain profile views on a flight display.
It is an object of the present invention to provide a pilot a means and method to select and display a swathe width of a vertical terrain profile view.
It is an advantage of the present invention to provide a pilot a means and method of selecting a side-on and end-on vertical terrain profile view.
It is an advantage of the present invention to provide a pilot a plan view showing a selected vertical terrain profile swathe width.
It is a feature of the present invention to present terrain information in color with red indicating terrain at an altitude equal to or greater than that of an aircraft.
It is a feature of the present invention to present terrain information in color with yellow indicating terrain at an altitude within a predetermined distance below an aircraft.